Anniversary Narrows Slot Canyon is located within the Lake Mead Scenic Byway area, just outside of Las Vegas, Nevada. Hiking this trail is best November through March when the temperatures are much cooler.
Turtlehead Peak (6, 323 ft) is located in Red Rock Canyon National Conservation Area, and one of the most popular hikes in the park. To reach the trailhead (TH) you must have a timed entry reservation for Red Rocks (get that here), and start hiking early to beat to people all the people and weather. Turtlehead Peak offers amazing views of the entire area, and on a clear day you can even see the Las Vegas Strip!
Lexington Arch is located within Great Basin National Park, yet very few people make the trek to it due to it not being in the main area of the N.P. In fact, access to the trailhead was closed for a long time due to the "Strawberry Fire" of 2016. Then a flash flood ripped up the road leading to the original TH. Now, hikers have to add an additional mile of hiking before reaching the official TH.
Meridian Peak (5,978ft) is small peak in North Salt Lake along the Bonneville Shoreline Trail and just north of Ensign Peak. The main trail also takes you past Matt's Arch (aka "Industrial Arch") - a tiny natural arch made of limestone.
Paul Bunyan's Woodpile is an interesting geological feature in Central Utah, that looks like a "woodpile" of logs left behind by the giant lumberjack of American & Canadian Folklore. Really the woodpile is a cluster of lava rocks formed about 30 million years ago; the logs were then formed into orderly columns.